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'Artificial leaf' could power communities of the future

The world could one day be powered by photosynthesis from artificial leaves, say researchers from Monash University in Melbourne. Their system to turn water into fuel, using nothing but solar energy, could be used to run cars, houses and even whole communities.

The 'artificial leaf' created by researchers is actually more of a solar-powered device that is able to produce hydrogen with a record-breaking degree of efficiency. The details of the technology, which marks a massive step towards simulating practical, artificial photosynthesis, have been laid out in a paper published in the journal Energy and Environmental Science.

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The process involves basically splitting up the water by passing an electric current through it, separating out the hydrogen particles so they can be used for fuel. While it sounds expensive, it is apparently cheap to do, and results in one of the cleanest forms of energy, which contains no carbon and produces no carbon dioxide as a by-product. "Hydrogen can be used to generate electricity directly in fuel cells. Cars driven by fuel cell electric engines are becoming available from a number of car manufacturers. Hydrogen could even be used as an inexpensive energy storage technology at the household level to store energy from roof-top solar cells," explains Professor Doug MacFarlane, co-author of the paper.

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When water is converted in hydrogen to serve as fuel, the success of the process is judged on its efficiency -- if it's too slow, or too expensive, it's not practical. The photosynthesising must conserve at least 10 percent of energy for it to be worthwhile. This efficiency rate has already been surpassed by other efforts, but the researchers from Monash have managed to achieve an efficiency in excess of 22 percent -- by the far the highest ever seen, though not quite enough to make it financially viable... yet. "This simple and adaptable system addresses key criteria for the large-scale deployment of an artificial photosynthesis device," claim the researchers in the paper's abstract.

With the increased effort to find alternatives to traditional fossil fuels, trying to mimic the natural process that all human life relies on seems like a savvy option, and one that scientists have been working on for many years now. "Electrochemical splitting of water could provide a cheap, clean and renewable source of hydrogen as the ultimately sustainable fuel. This latest breakthrough is significant in that it takes us one step further towards this becoming a reality," said lead researcher Professor Leone Spiccia.